Below is the full text of the interview the head of the International Atomic Energy Agency (IAEA), Mohammad ElBaradei, gave to BBC correspondent Jim Muir in Tehran on Thursday.

Q: The Iranians invited you to come at this crucial time, presumably because they had something to say. What did they tell you?

A: I was assured that they have made a decision to come with full and complete story of all the nuclear activities in the past, and that they are absolutely ready now to co-operate fully with us and to demonstrate full transparency, for us to be able to get all the clarification required.

Mind you, we have been working here for a year, we have made some progress but there are still a lot of important outstanding issues that have not been resolved, that have to do with their past nuclear activities, particularly in the area of enrichment of uranium which is the most sensitive part of the fuel cycle.

So we have been at it with the Iranian authorities trying to seek all the
information.

In the past, as I reported to our board of governors, information has been slow in coming, has been reactive in nature, and I was told that's going to change, that in the next few days we are getting the full, complete picture, and that if that were to happen, I think that would be very positive.

Q: Does that imply in a sense that they've been less than forthcoming in the past? They haven't been moving fast enough, have they been trying to hide things?

A: I think the process has been very slow. We had to extract the information, the information sometimes has changed, and it has been slow process.

And this is an important, sensitive issue we're dealing with, and as I reported to our member states, it is urgent and essential Iran gives us full co-operation and demonstrates through verification that they are clean, that their programme is for peaceful purpose.

Today I've been assured that this is going to happen, that decisions has been made to come forward with all the information we need, and if that were to happen in the next few I think that would be a breakthrough, a very positive move forward.

Q: Even if that means for Iran making some embarrassing admissions, is that the feeling you have?

A: Let the chips falls as they may. I think they have been saying that of course they had had to do things in their own way because of the sanctions over the last 20 years, that they had to get things over the black market, and sometime they had not to declare things because that might have meant stopping any imports of sensitive equipment.

I've reported failures in (Iran's) reporting to us in the past. There might be new failures, but I think at the end of the day it's in the interest of Iran to come clean and to - even if there are certain admissions - to admit everything, for us to take the corrective action necessary, and to demonstrate that everything is on board, under safeguard.

I think that's much better than continuous questions marks about the nature and extent of Iran nuclear programmes, and the consequences of that obviously will be much worse than admitting certain mistakes.

Q: How optimistic are you at the end of this really quite crucial visit that by the end of the month (31 October) you will have what you need to certify that Iran is clean?

A: I hope at least we'll get all the information, we need all the information and as I said before it is not negotiable that we get all the information before the end of the month.

We've been here for a year, the credibility of this verification system requires that by that time we need to have all the information.

Whether we will be able to complete our verification process (before the deadline) - that's a different question. It might take us a little bit more time to verify the information we have, but that's our problem.

But I will not compromise on the need for Iran to come with the full story, comprehensive information, in the next couple of weeks and I was assured that this was going to happen, that they will come forward, and we'll see.

Q: Now you're talking essentially about the past. You're trying to understand by the end of the month exactly what Iran has been up to and is up to. Looking to the future and the question of the additional protocol which would give you tougher inspection rights or practices, what have you been told about that, will Iran sign?

A: They said that they are ready to sign, they still have certain clarifications they are seeking.

I think the protocol has become a national issue here, emotional issue, the feeling that the protocol will be used and abused to undermine Iran's sovereignty, Iran's security, dignity, religious belief.

I spent some time today dispelling these misconceptions. I made it very clear that the protocol is simply an instrument we need, to make sure that all nuclear activities in a country, Iran or otherwise, are dedicated for peaceful purposes.

We use all the authority we have in a judicious manner, in an impartial manner, and it is not meant at all to undermine sovereignty or security or any irrelevant information that is not linked to our activities.

I think they were happy to hear that, I think we probably need to make that in public as and when they decide to sign the protocol. But they have said that they are ready to sign the protocol, we have a team coming here early next week again to discuss with them whatever apprehensions they have, and I hope again in the next couple of weeks we'll see a positive decision by Iran to sign the protocol.

We need to clarify the past, we need to regulate the future. For clarifying the past, it is very important that we get a full and complete declaration. Regulating the future requires that we have the necessary authority under the protocol to make sure that things in the future will continue to be dedicated for the peaceful purpose.

Q: You mentioned the issue of enrichment which is quite a sensitive issue for the Iranians. They demand that they should have the right to enrichment. I understand that some European countries have been trying to assure Iran that if it suspends its enrichment activities, they may look favourably on the idea of supplying enriched fuel to Iran and that there have been in fact envoys here from Britain, France and Germany in the last few days, to reinforce that message. Is that allaying their anxieties or their concerns on that?

A: Well that's a much more complicated issue because, on the one hand, of course they have the right under the non-proliferation treaty, every country has the right under non-proliferation treaty to have enrichment of uranium or reprocessing of plutonium.

However, we also know that this is a very sensitive part of the fuel cycle and a country that acquires this technologies runs very close to nuclear capability. So there are always concerns about running this part of the fuel cycle and in fact I am advocating myself that such a sensitive part of the fuel cycle should be under multilateral control, not only in Iran but everywhere else, because the margin of security becomes very slim if you have enrichment or reprocessing capabilities.

I am aware that there are discussions between Iran and some of the European countries to try to see whether in fact, to defuse the security concern, Iran might get assurance of supply, might get nuclear technology for electricity generation, without however having to do the fuel cycle itself and rather rely on very iron-clad guarantees that they would get assurance of supply of the fuel they need in the future.

However, that's not part of my portfolio. I'm following that but of course it has an impact on my work.

I hope however that such settlement will be possible in the future. I think it would be a win-win situation. Iran will get the energy needs they have, however without raising an anxiety about any sensitive fuel cycle activities here, and that might open the way in fact to a new chapter in the relationship between Iran and the West, particularly Europe.

As you know, there is a trade agreement in the making between the European Union and Iran. It's very much dependant on a very good successful resolution of the nuclear issue, so a settlement of all of the nuclear issues or crisis or whatever you want to call it, I think it will open a door for a new chapter in the relationship between Iran and the west which I think it would be positive and very good for Iran from my own perspective.

Q: Time is running out, isn't it? This is a real deadline, is it not?

A: I think the international community is getting impatient that they need to see that issue come to a closure.

As I said, after a year dealing with such a sensitive issue as whether Iran has declared all the nuclear activities to do with enriching uranium to the agency or not, I think the international community is determined that by the end of this month Iran has to provide all the information they have to the Agency in a full and comprehensive manner and I think the Iranian authorities understood that.

I made it very clear to them that this is non-negotiable - I won't be able to go to the board and say: "Give me more time because Iran has not provided information."

Once a decision has been made to provide the information, it should not take more than a week to give us all the information. It might take us much longer to verify, but we need the information to start moving forward with the verification process.

Q: So it is a very crucial turning point that Iran faces. If you, with everything that you know, have to guess which way it will go, what are the chances do you think that they will go in the direction that you want?

A: If I make an educated guess, or an educated gut feeling, I think a decision has been taken here that they need to put the past behind them, they need to move forward and clear all these issues which have a lot of ramifications for them, not only in the nuclear field but in terms of trade, commerce and others.

So I think they would like to clarify these issues, they would like to assure the international community about their nuclear programme. But they are still studying the ramifications for that, clearly they would like to make sure that this will not have an impact on their national security or dignity or sovereignty.

These are issues which are understood and that's why they are now in the beginning of dialogue between them and the Europeans, which I think is the only way to move things forward. So I am cautiously optimistic, I should say that.